“Viking Lander 2 took this color picture of the sky at the Utopia landing site Jan. 16, 1977. The view is possibly toward the south/southeast. The picture was taken about noon local lander time. The Sun is just outside the picture to the left, and its brightness has saturated the camera’s sensors. Opacity of the atmosphere has increased with the onset of autumn in northern hemisphere of Mars. Less light now penetrates the atmosphere than during the primary mission period last summer. There are two primary causes: an ice fog develops during the night and lasts through the morning. Soil particles suspended in the atmosphere have also increased. Extremely fine soil particles suspended in the atmosphere preferentially absorb blue light, producing the reddish color of the Martian sky.”
The above is per the caption I found for what I think to be a companion/associated image, with my editorial 'revision' based on what’s in the photograph.
Confirmation of it at least being Utopia Planitia:
www.msss.com/mars/pictures/viking_lander/l2c1pmq2q3.jpg
Credit: Malin Space Science Systems website